Comparing the iPhone 7 and iPhone 8 pages from last week to today, Barclays analyst Blayne Curtis wrote in a note he had found that Apple "will remove the dongle (~$1.00 CRUS content) from its entire suite of phones."

Apple's older iPhones would no longer include lightning-to-headphone jack adapters, the company's website showed on Thursday, which according to Barclays would hurt audio chip supplier Cirrus Logic. Shares of Cirrus, which makes analogue chips used in Apple devices, fell 3.8 percent to $39.46. In fiscal 2018, Apple accounted for about 81 percent of Cirrus total sales.

Cirrus did not immediately respond to request for comment and Apple declined to comment. Comparing the iPhone 7 and iPhone 8 pages from last week to today, Barclays analyst Blayne Curtis wrote in a note he had found that Apple "will remove the dongle (~$1.00 CRUS content) from its entire suite of phones."

"While CRUS did admit the dongle was out in current generations, it's an additional negative that they are also removing the dongle from the older products," Curtis said. Apple introduced three new iPhones, including its largest-ever iPhone and a watch that detects heart problems on Wednesday.